12-31-2018, 01:31 PM
Hi Matthew,
>Green arrow points to the lead from the center tap of the power transformer. This is 400 volts, correct?
Not so much when it's all wire back up correctly it's abt -17vdc
1 The lug that the green arrow is pointing to is the negative terminal from one of the filter caps (86 or 87), I'm thinking that was two of them originally one for each cap.
Yes 75 has the + side connected to the chassis and it is lower voltage that the others. It's there to filter and decouple the -bias for the 42 tubes
>I am assuming that the bottom-most tap on the voltage divider resistor #81 is not grounded (because is is offset by a fiber/felt washer).
The end isn't grounded cause if it was it wounld ground the ct of the transformer and kill on any bias voltage.
> If I want to use two caps instead of a single 0.3 uF as a replacement (i.e., keeping the jumper and the outward appearance), which terminal has the common end of the two caps? It seems that it should be terminal nearest the mounting lug (i.e., the one without the jumper from the end terminal), but can anyone confirm this?
My best recollection is that the two .15 cap are connected together inside the bakelite block and doesn't have a jumper. Just connected to the block terminals.
Here's the cliff notes for the cap connections
>Green arrow points to the lead from the center tap of the power transformer. This is 400 volts, correct?
Not so much when it's all wire back up correctly it's abt -17vdc
1 The lug that the green arrow is pointing to is the negative terminal from one of the filter caps (86 or 87), I'm thinking that was two of them originally one for each cap.
Yes 75 has the + side connected to the chassis and it is lower voltage that the others. It's there to filter and decouple the -bias for the 42 tubes
>I am assuming that the bottom-most tap on the voltage divider resistor #81 is not grounded (because is is offset by a fiber/felt washer).
The end isn't grounded cause if it was it wounld ground the ct of the transformer and kill on any bias voltage.
> If I want to use two caps instead of a single 0.3 uF as a replacement (i.e., keeping the jumper and the outward appearance), which terminal has the common end of the two caps? It seems that it should be terminal nearest the mounting lug (i.e., the one without the jumper from the end terminal), but can anyone confirm this?
My best recollection is that the two .15 cap are connected together inside the bakelite block and doesn't have a jumper. Just connected to the block terminals.
Here's the cliff notes for the cap connections
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry
